Electrical heating device



MayV 29,1923. y 1,456,878 M. M. KOHN ELECTRICAL HEATING DEVICEv FiledJan.A 28; 1921 ."5 Sheets-Sheet l 1,3 ,20 "ffii/,3^:v/H12'f c il? aJ- lT9 an v v v l: 000000000004 00000000000 l 000000000004 l o 00000000000 Q000 0000000 000000000004 000000000000000 0%@ A A AOAOLQAOAAOAOAOAOA 19213 .sheets-sheet 2 v M M KOHN l ELECTRICAL HEATING DEVICE File Jan. 28.

May"29, 1923.

Patented May'fzaisze. l

PATENTA OFFICE..

MILTON H. KOEN, F NEW YORK, N. Y.

ELECTRICAL HEATING DEVICE.

Application led January 28, 1921. Serial No. 440,841.

To`all whom t *my concer/1.:

B e it known that I, MILTON M. KoHN, a v citizen of the United States,residing at New York, in the county of New York and State of lNew York,have invented certain new and useful Im rovements in Electrical HeatinDevices, o which the following is a speci cation. f

-This invention relates to portable electric heating and cookingdevices, and particularly such as may be used for toasting bread andcooking other articles of food.

In general my device consists of a` cas ing consisting preferably ofheat insulating walls surrounding a series of easily detachable andremovable and interchangeable heating units, the space between theheating -units being occupied by the material to be cooked, for example,a slice of bread or a receptacle containing a beverage, whereby the foodor beverage is heated upon both sideswhich comprise a very great part of-the area. As a. result of my structure the slice of bread or beverageor other material, receiving heat over practically @its sentire surface,requires less intensity of heatwn the heating element. In fact, goodresults may be produced with the intensity so low that the heatingelement while functioning does not glow and by reason thereof a very lowpriced resistance and, hence, low priced heating unit may be used. l e

While in most devices of this t pe ex pensive resistance alloys arerequire in my device I mayuse either such alloys or ordinary iron Wire,or in fact any other desired resistance material, as it will last agreat length of time, due to the fact that it is not necessary to heatit to a glowing temperature.

The drawings show two embodiments of my invention which are merelyillustrative thereof. Further modifications may be made withoutdeparting from the spirit of the invention,` providing the essentialfeatures are preserved. Fig. 1 lof the drawing is a verticall'ongitudinal section of one form of construc-A tion.

Fig. 2 is 'a sectional line 2-2 of Fig. 1.

Fig. 3 is a longitudinal vertical section of a diierent form ofconstruction.

plan view thereof on -tion of the arrow Fig. 4 is a sectional planthereof on linev 4 4 of Fig. s.

Fig. 5 is a sectional view of a modificat1on of my device. v

Fig. 6 1s a view of one side of the assemblage andwiring Aplate viewedin the direcon Fig. 5. F 1g. 7 1s a view of the opposite side of saldplate.

Referring to Figs. 1 and e, 1o is a double walled casing consisting ofan internal wall 11 and an external wall 12 having insulating material13 therebetween, the casing being mounted if desired on suitablesupports 14. The size vand form of4 the casing may be such as is foundmost desirable, but in general I prefer that the interior width anddepth be such as to accommodate an ordinary slice of bread or otherarticles as it may be desired to cook ---sixn ultaneously. Within thecasing are the desired number of heating units 15, which may be of anystructure but preferably consist of a cheap resistance material embeddedin a suitable plastic composition, which may be such as is described inmy co-pending application Serial No. 447,122, filed Feb. 23, 1921. SinceI do not herein claim the structure of said heating element per se Ideem it unnecessary to further describe the same other than to statethat this element has attached thereto suitable means for attaching itremovably and interchangeably within the casing and means for completingthe electric circuit. v

In this particular embodiment of the invention the units may havesuitable supporting pins 16 passing therethrough, such supporting pins16 having knurled heads 17 at one end and screw threads 18 at the other,

the elements being supported between these heads and screw threads. 'Awall, for example that -to the right of Fig. 1, is provided withsuitable perforations through which pass electrically conducting sleeves19, each having a flange 20 at one endv and screw threads 21 at theother. These sleeves fit within the aforesaid openings, suitablyinsulated therefrom, as by a sleeve 22 of insulating material. A nut 23binds the sleeve in position in the wall and a second nut 24 holds theelectrical lead (not shown) in electrical contact with the nut 23,thereby this contact may be increased by screwingm the pin 16 by meansof the knurled head 17.

In order to remove or re lace any of these heating elements, it is sucient to give the knurled heads 17 thereof a ew turns, where? upon thepins together with the element may be removed bodily from the rest-ofthe device, and a heating element may be operatively inserted with thesame facility.

To facilitate movement of the pin within the heating element, the lattermay be provided with suitable tubes 27 embedded therewithin, throughwhich the pin 16 may easily slide.

The front of the casing is open and adapted to be closed by a closureelement 30, which also may consist of two walls 31 and 32 having betweenthem suitable insulating material 33 and for convenience a handle 34.Said closure element' is provided with food supporting members, so thatthe various articles of food or beverage are placed within the device bythe mere closing of the closure element. suitably attached to theclosure element 30 is a plate 35, which is adapted to slide within agroove 36 of the casing 10. Suitably supported `upon the door and member35 are the supporting members 36, which may consist of any suitablesupports for the sides of the article, but preferably are made ofexpanded metal, as shown. wo of these are located betweenV each twoheating elements, spaced apart to accommodate the bread, beveragecontainer or the like, and connected to each other at the inner end byelements 37 the assemblage forming a sort ot cage into which the articlemay be introduced and supported very close to but out of contact withthe heating element. Suitable notches 38 may be provided to facilitateremoval or introduction of the article to be cooked. The.

form of construction illustrated in Figs. V3 and 4 is, in general,similar to that just described.

It desired, the casing, which also has double walls, may be made airtight and evacuated, or air may be used as the insulating medium.

In the embodiment illustrated on Figs. 3 and 4 the heating elements areattached to and movable with the closure member, and serve as supportsfor the article of food o r container which is to receive the heatthere'- from.

The door 40, which may be double walled v intacte like the'container, isprovided with homes 41 suitably screw threaded to receive the screwthreaded ends 42 of the pins 43, upon which pins the heating elementsare supported as in the form of construction previously described. Thisdoor also has a plate 35 sliding within the roove 36, as in the otherembodiment. The heating elements have projecting terminals 44, which maybejof the split pin or other suitable type, and which register and makecontact with terminals 45 insulatedly retained in the rear wall of thecasing by the sleeves 46.

It will thus be apparent that by means of this modification thepositioning of the closure element/to close the opening will suitablyplace the material to be heated, and at the same time make electricalContact between the heating units and the terminals upon the casing. n

ln Figs. 5, 6 and 7 I have illustrated a modification in which theheating units are suitably attached to an assemblage and wiring plate60. rlhis plate is provided with suitable electrical contacts 61 and61a, which register with corresponding insulated contacts 62 retained inthe casing wall by means of insulated sleeves 63, and which serve asterminals for the completed device. Plate 60 is preferably perforated.

On the side of the plate opposite that provided with the contacts 61 and61L are a number of fixed contacts which pass through the plate to formremovable contacts and supporting means for the heating units.- By 10omeans ,of this arrangement any one or more of the heati units may beremoved from the assemble device, or all the units together with theassemblage and wiring plate may be removed as a whole. This modiiica-105 tion has certain advantages over those previously described, namely,that upon insertion of the assembled heating units and plate into thecasing only two sets of contact need register, which reatly facilitates1210 accurate insertion of the heating parts.

In devices of this type the centre will become considerably hotterthan'the ends when each unit generates thesame amount ot heat;accordingly I prefer to cause each ot the 115 two outside units togenerate more heat than any of the inside units. This may beaccomplished by various methods, that which I prefer being to divide theheating circuit/into more than one circuit, and pref-v 12o erably byhaving the outside units in one circuit and the other' units in anothercircuit which has a greater resistance than the first mentioned circuit.A preferred method of accomplishing this is as follows.

The Contact 61 is connected by means of a wire 64 with the contact orbinding post 65, which in turn is connected by means of the wire 66 withthe binding post 67. A binding post 68 is opposite binding post 67 andv130 78 and. opposite binding post 76 is a binding post 79; posts 78 and79 are connected to-` gether by means of a wire80. 1

All the above mentioned binding posts aref' 'located on the same side ofplate 60, and

connected to each binding post there is a quick detachable contact 81projectngfrom the other side of said plate. v

The heating units are provided with contacts to register with contacts81, and are arranged upon the plate 60 by locating them across the'pairs of opposite contacts. This `will cause a division of the circuit,so that the current entering at 61 will iow through wires 64 and 66 tothe binding post 67,

through a heating unit to the binding post 68, then through the wire 69and binding post 70, thenthrough another heating unit to the bindingpost 71, through wire 72 to the binding post 73, and through anotherheating unit to the vbinding post 74, and then on and out throughcontact 61. 'I he other circuit will branch oii' at the'binding 4. post65 and passthrough a heating unit to the binding post 78, thenthroughvwire 80 to the binding post .79, then through another heating. lunit tothe 'binding post 76, and then through wire 77 to the contact 61a.

Iii-.any modification the slice of bread or vessel 5() containing beveraeor the like is suitably heated from practically all sides.

I claim:

f1. An electrical heating device compi-isi' ing a casing,quicklyremovable, replaceable and-'interchangeable heating units, quickdetachable .connectors each comprising two parts, one of which isremovable with the heating unitsand the other of which is attached tothe casing and constitutes a terminal.

2. An electrical heating devicel compris ing a casing, a part of a quickdetachable connector on said casing and constituting a terminal, aremovable, replaceable and interchangeabl heating unit, another part ofal quick detachable connector attached to said heating unit andcorresponding to said rst mentioned part.

3. An electrical heating device comprisinga casing, parts of two quickdetachable connectors on said casing and constituting terminals,a"removable plate,l two parts of quick detachable connectors,corresponding to saidlfirs't mentioned parts, on said plate, a series ofconnector parts on said plate, a series of heating units each having aconnector part corresponding to those of said series, and electricalconnections on said plate.

4. In an electric heating y device of the type described, a doubleWalled heat insulated casing, quick-'detachable' electrical heatingunits electrically attached conductively within said casing'to a wallthereof, one side of said casing being open and...l

adapted to be closed when operative .by fan insulated double walleddoormounted'on a plate horizontally slidable'in' said casing,

saidplate being provided with racks for supporting the material to beheated.

5. In anfele'ctric heating device of the typedescribed, a casinghavinginternal and external walls insulated fromeach other, a double-walledinsulated element forming a' closure'or said casing and closinganelectriccircuit when in the closed osition, said closure beingfmountedon a p ate horizontally slidable in said casing, electrical heat# ingunits mounted on said plate, terminals lin-'said heating unitsregistering with terminals in the rear wall of said casing to close thecircuit, said horizontal slidable plate flormiig the supports Afor the`material to'be eate 6. YAn electrical heating device comprising t acasing, a multiplicity of heat'ng units ssj within saidl casing soarranged-as to leave A heating spaces between said units, and means tocause each of the outer units to ,generate 'more heat than each of theinter# mediate units.

ico

7. An electrical heating device comprising a casing, a multiplicity ofheating units within said casing so arranged' as toleave heating spacesbetweensaidunits. thev outer units being connected in' onecircuit,intermediate units connected in another-cireuit, the resistance of thefirst mentioned VVcircuit being less than that of said second mentionedcircuit.v Y. 3

8. An electrical heating device comprising a casing, a multiplicity ofheating units within said casing so arranged as'to leave heating spacesbetween said units, electrical terminals on said casing, a distributingand supporting` plate. quick-detachable connections between said plateand said terminals,

electric connections from said quickdetachwithin said casing so arrangedas to leave heating spaces between said units, electrical terminals onsaid casing, a distributing and supporting plate. quick-detachableconnections between said plate and'said terminals,

electric connections from said quick-detachable connections comprisingtwo circuits,

one of said circuits including the outer heating units and the othercircuit including intermediate heating units, the second mentionedcircuitl including more heating units than the first mentioned circuit.

10. In an electrical heating device of the type described, a doublewalled heat insulated casing, quick detachable 'electrical heating unitselectrically attached Within said casing to a wall thereof, one side ofsaid casing being open and adapted to be closed when operative by aninsulated double walled door mounted on a plate slidable in said casing,said plate being provided with racks forsuporting the material to beheated. f

Lemme 11. In an electric heatin device of the type described, a casinghaving internal and external Walls insulated from each other, a doublewalled insulated element formin a closure for said casing and closing;an eectric circuit when in the closed position, said closure beingmounted on a plate Slid'a'ble in said casing, electrical heating unitsmounted on said plate, terminals in said heating units registering withterminals in the rear Wall of said casing to close the circuit, saidplate forming the supports for the material to be heated. l

iin testimony whereof li ail-1X my signature.V

MLTON M. KUHN.

